This writeup contains a list of troubles your character can
experience in a game of Nethack, and the ways I can think of to
fix them. I've organised them according to how serious they are in
the eyes of your deity. If your alignment is reasonably good and
your luck is non-negative, then a successful prayer is guaranteed
to fix all your major problems. Once your luck is high enough (at
least 3) a successful prayer is also guaranteed to fix all your
minor problems. So prayer will not be mentioned specifically in the
remainder of this writeup.

Major troubles (in your deity's eyes)

Turning to stone

In addition to what Jeeves says, you can drink a potion of acid,
or polymorph into any stoning-resistant monster.

All you can do is pray or polymorph into something which can eat
unusual things, such as a rock mole or xorn. The time to create
food with stone to flesh is before you are too weak to cast it.

Lack of hit points

For your deity to recognise this as a trouble, your hit points
must either be 5 or less, or 1/7 of their maximum value or less. If
your hit points are rapidly dropping and prayer won't help, do NOT
keep fighting in the hope that one last swing will kill it. Stop
and think about what your best strategy for survival is.

Run away if you're fast enough, retreat into a corridor so that
you need only face one enemy at a time, or teleport away. Level
teleport, dig through the floor, or quaff a cursed potion of gain
level, but remember, some monsters will follow you when you escape
in these ways.

Your deity only recognises this as a trouble in Slash'Em. It can
be cured by drinking a potion of gain energy, reading a scroll of
charging while confused, or in Slash'Em, using the draw energy or
power surge technique.

Troubles not recognised by your deity

There are three intrinsics which Nethackers sometimes see as bad but
which your deity will not treat as problems to be fixed. They are
uncontrolled teleportitis (randomly teleporting around), aggravate
monster acquired by cannibalism or eating a domestic animal, and
occasionally invisibility. The only way to lose these intrinsics is
to play with a gremlin at night, which is not recommended as you
will probably lose some useful intrinsics first.

However, these "bad" intrinsics can all be brought under control.
Once you have teleport control teleportitis becomes a good thing.
The effects of aggravate monster are not very serious and are
negated by stealth. Invisibility is only a problem because it makes
it harder for you to enter shops, and this can be solved by wearing
a mummy wrapping.